Machine learning methods for generating high dimensional discrete datasets

The development of platforms and techniques for emerging Big Data and Machine Learning applications requires the availability of real-life datasets. A possible solution is to synthesize datasets that reflect patterns of real ones using a two-step approach: first, a real dataset X is analyzed to derive relevant patterns Z and, then, to use such patterns for reconstructing a new dataset X ' that preserves the main characteristics of X. This survey explores two possible approaches: (1) Constraint-based generation and (2) probabilistic generative modeling. The former is devised using inverse mining (IFM) techniques, and consists of generating a dataset satisfying given support constraints on the itemsets of an input set, that are typically the frequent ones. By contrast, for the latter approach, recent developments in probabilistic generative modeling (PGM) are explored that model the generation as a sampling process from a parametric distribution, typically encoded as neural network. The two approaches are compared by providing an overview of their instantiations for the case of discrete data and discussing their pros and cons. This article is categorized under: Fundamental Concepts of Data and Knowledge > Big Data Mining Technologies > Machine Learning Algorithmic Development > Structure Discover

Long wavelength optical control of glutamate receptor ion channels using a tetra-ortho-substituted azobenzene derivative

A tetra-ortho-chloro substituted azobenzene unit was incorporated into a photoswitchable tethered ligand for ionotropic glutamate receptors. This compound confers the modified protein with the unusual optical responses of the substituted azo scaffold permitting channel opening with yellow and red light and channel closing with blue light

Early histologic findings of pulmonary SARS-CoV-2 infection detected in a surgical specimen

Despite the current pandemic season, reports on pathologic features of coronavirus disease 19 (Covid-19) are exceedingly rare at the present time. Here we describe the pathologic features of early lung involvement by Covid-19 in a surgical sample resected for carcinoma from a patient who developed SARS-CoV-2 infection soon after surgery. The main histologic findings observed were pneumocyte damage, alveolar hemorrhages with clustering of macrophages, prominent and diffuse neutrophilic margination within septal vessels, and interstitial inflammatory infiltrates, mainly represented by CD8+ T lymphocytes. These features are similar to those previously described in SARS-CoV-2 infection. Subtle histologic changes suggestive pulmonary involvement by Covid-19 may be accidentally encountered in routine pathology practice, especially when extensive sampling is performed for histology. These findings should be carefully interpreted in light of the clinical context of the patient and could prompt a pharyngeal swab PCR test to rule out the possibility of SARS-CoV-2 infection in asymptomatic patients

Black and pink. Single lesion or double diagnosis?

Fibroepithelioma of Pinkus (FeP) is an uncommon skin lesion considered to be a rare variant of basal cell carcinoma (BCC), even though some researchers have argued for its classifica- tion as a trichoblastoma. FeP appears frequently as a solitary, flesh-colored, well-demarcated plaque, typically localized on the lumbosacral area of patients aged 40 to 60 years. It often develops in patients with a history of BCC, most commonly in wome

Liver infection and COVID-19: the electron microscopy proof and revision of the literature

OBJECTIVE: COVID-19, the newly emerging infectious disease, has been associated with acute liver injury, often related to progression to severe pneumonia. The association between moderate-severe liver injury and more severe clinical course of COVID-19 has suggested that liver injury is prevalent in severe than in mild cases of COVID-19, while no difference in liver involvement has been reported between survivors and non-survivors. The spectrum of liver involvement during COVID-19 ranges from an asymptomatic elevation of liver enzymes to severe hepatitis. Only rarely, cases with acute hepatitis have been reported in the absence of respiratory symptoms. Both epithelial and biliary cells possess the angiotensin-converting enzyme-2 receptors that SARS-CoV-2 uses to be internalized. However, to our knowledge, no ultrastructural identification of the virus in liver cells has been reported to date. Here we provide evidence of SARS-CoV-2 in the liver of two patients, a 34-year-old woman and a 60-year-old man with COVID-19.PATIENTS AND METHODS: We investigated two patients with COVID-19 showing several virions within cytoplasmic vacuoles of cholangiocytes and in endothelial cells of hepatic sinusoids. In both patients, we performed histological and ultrastructural examinations by liver biopsy. After two months, both patients were free of symptoms, and the SARS-CoV-2 infection had resolved.RESULTS: Liver biopsy histological and ultrastructural examination showed liver injury and several virions within cytoplasmic vacuoles of cholangiocytes and in endothelial cells of hepatic sinusoids.CONCLUSIONS: Although most studies in COVID-19 have been focused on the lungs, recently, cholestatic liver pathology has been introduced in the spectrum of pathological changes related to COVID-19. To the best of our knowledge, those presented in this paper are the first images of hepatic SARS-CoV-2 infected liver cells. Our findings suggest a role for cholangiocytes and biliary structures in the COVID-19

Long wavelength optical control of glutamate receptor ion channels using a tetra-ortho-substituted azobenzene derivative

A tetra-ortho-chloro substituted azobenzene unit was incorporated into a photoswitchable tethered ligand for ionotropic glutamate receptors. This compound confers the modified protein with the unusual optical responses of the substituted azo scaffold permitting channel opening with yellow and red light and channel closing with blue light

An advanced sheep (Ovis aries, 2n = 54) cytogenetic map and assignment of 88 new autosomal loci by fluorescence in situ hybridization and R-banding

Presented herein is an updated sheep cytogenetic map that contains 452 loci (291 type I and 161 type II) assigned to specific chromosome bands or regions on standard R-banded ideograms. This map, which significantly extends our knowledge of the physical organization of the ovine genome, includes new assignments for 88 autosomal loci, including 74 type I loci (known genes) and 14 type II loci (SSRs/microsatellite marker/STSs), by FISH-mapping and R-banding. Comparison of the ovine map to the cattle and goat cytogenetic maps showed that common loci were located within homologous chromosomes and chromosome bands, confirming the high level of conservation of autosomes among ruminant species. Eleven loci that were FISH-mapped in sheep (B3GAT2, ASCC3, RARSL, BRD2, POLR1C, PPP2R5D, TNRC5, BAT2, BAT4, CDC5L and OLA-DRA) are unassigned in cattle and goat. Eleven other loci (D3S32, D1S86, BMS2621, SFXN5, D5S3, D5S68, CSKB1, D7S49, D9S15, D9S55 and D29S35) were assigned to specific ovine chromosome (OAR) bands but have only been assigned to chromosomes in cattle and goat